Markdown to HTML Converter API

Content

Convert Markdown to HTML instantly with full control over formatting options. Support for tables, task lists, strikethrough, emojis, and more.

Authentication

All API requests require a valid API key passed in the Authorization header as a Bearer token.

Rate Limit

100 requests per minute

Endpoints

1 endpoint available

Overview

The Markdown to HTML Converter API transforms Markdown content into HTML with extensive formatting options using the Showdown library.

Features

Convert Markdown to clean, valid HTML
Support for GitHub-flavored Markdown extensions
Configurable options: tables, task lists, strikethrough, emojis, and more
Auto-link URLs, encode emails, and open links in new windows

Use Cases

Convert README files for web display
Process blog posts written in Markdown
Generate HTML documentation from Markdown sources
Integrate Markdown processing into CMS workflows

Endpoints

POST

/v1/tools/markdown-to-html

Convert Markdown content to HTML

Request Body

Content-Type: application/json

Parameter	Type	Required	Description
markdown	string	Required	The Markdown content to convert
options	object	Optional	Conversion options (all boolean, default false unless noted)
options.simplifiedAutoLink	boolean	Optional	Automatically convert URLs to links
options.strikethrough	boolean	Optional	Enable ~~strikethrough~~ syntax
options.tables	boolean	Optional	Enable GitHub-style tables
options.tasklists	boolean	Optional	Enable GitHub-style task lists
options.ghCodeBlocks	boolean	Optional	Enable GitHub-style fenced code blocks (default: true)
options.simpleLineBreaks	boolean	Optional	Convert single line breaks to <br>
options.emoji	boolean	Optional	Enable emoji shortcode support :smile:
options.encodeEmails	boolean	Optional	Encode email addresses for spam protection (default: true)
options.openLinksInNewWindow	boolean	Optional	Add target="_blank" to links
options.completeHTMLDocument	boolean	Optional	Wrap output in full HTML document structure

Response Example

{
  "success": true,
  "data": {
    "html": "<h1 id=\"hello-world\">Hello World</h1>\n<p>This is <strong>bold</strong> and <em>italic</em> text.</p>\n<ul>\n<li>List item 1</li>\n<li>List item 2</li>\n</ul>",
    "inputLength": 78,
    "outputLength": 156
  }
}

Error Codes

400

Bad Request - Missing markdown content

401

Unauthorized - Invalid or missing API key

429

Too Many Requests - Rate limit exceeded

500

Internal Server Error

Code Examples

curl -X POST https://api.opentools.ca/v1/tools/markdown-to-html \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "markdown": "# Hello World\n\nThis is **bold** and *italic* text.\n\n- List item 1\n- List item 2",
    "options": {
      "tables": true,
      "tasklists": true,
      "emoji": true,
      "strikethrough": true
    }
  }'

Ready to get started?

Create an API key to start using the Markdown to HTML Converter API.